RoyalTek BT GPS mini RBT 1000

Twelve parallel channels
Support 2D/3D information
Cold/Warm/Hot start time: 45/38/8 seconds
MC Card connector for external GPS antenna
Support standard NMEA-0183 at 7,600 bps baud rate
Support standard SiRF binary at 4,800 bps
Compatible with Bluetooth devices with SPP (Serial Port Profile)

RoyalTek RTB 1000 connected to a Nokia 6600 running nmea_info.py

Izotope serial generator software. GPS product; RBT-1000 user manual; MBT-1100 user manual (log by button push) MBT-1100 user manual (log by time) RGM-2000 user manual; RTG-2000 quick guide; RFG-2000 user manual; RBT-2210 user manual; RBT-2300 user manual; RTA-3000 quick guide; RGM-3600 user manual; RGM-3800 user manual; RGM-4600 user manual; GPS module; REB-22R user manual; MEB. Gps Monitor Royaltek Software RoyalTek RBT-1000/1100 Manager v.1.0 An application can control and manager RoyalTek RBT-1000/1100(BT GPS mini) series Bluetooth GPS receiver using RBIN protocol.

RoyalTek BT GPS x-mini RBT-2100

Same as RBT 1000, but this one has a SiRFstarIII chip. Replacable LiIon battery (Nokia compatible)

SiRFstarIII GPS chipset
20 parallel channels
NMEA0183 compliant protocol
Extreme fast TTFF at low signal level.
High sensitivity acquisition
WAAS/EGNOS Supported (turned off by default, need to be ON using command sended in Sirf protocol (Using for example sirfdemo software), There are no NMEA-compatible commands to turn it on, only Sirf)

RoyalTek Mini Xtreme RBT-2110

Bluetooth device with SiRFstarIII chipset. Works out of the box under Linux. Very small, fits everywhere. Has useful rubber feets so it doesn't slide around in your car. Mine came with a car power adapter but no AC adapter. LiIon battery is replaceable.

SiRFstarIII GPS chipset
20 parallel channels
NMEA0183 compliant protocol
Extreme fast TTFF at low signal level.
High sensitivity acquisition

RoyalTek GPS x-mini II RBT-2200/RBT-2210

SiRFstarIII GPS chipset
20 parallel channels
NMEA0183 compliant protocol
Extreme fast TTFF at low signal level.
High sensitivity acquisition
Power saving features
Industrial Standard

RoyalTek RBT-2300

SiRFstarIII GPS chipset
20 parallel channels
650,000 trackpoints
Battery lasts 7 hours
NMEA0183 compliant protocol
Bluetooth
Works with Linux (Jdatalog)

Pros

Very cheap
Huge memory
You can use standard Nokia BL-4C batteries, more capacity

Cons

No waypoint button
Downloading data requires some knowledge
No segmentation (all trackpoints are saved together by day, even if you switch off & on)
- Its a configuration flag, you can append or create new trackpoints.
No on/off trackpoints switch
Only includes a car charger (but a 5 V 0.4 A charger is cheap)
- In my case it also has a USB connector

RoyalTek BlueGPS RBT 3000

Bluetooth GPS data logger — no screen, minimal indicator lights. I don't have any experience of another GPS, so I really like it.

Good things

Massive memory capacity — apparently it stores over 30,000 records. I have used it for a few hours every day on holiday and after two weeks still had spare capacity. I think you can fit more records on if you reduce the type of info it logs (not the frequency but the detail; e.g., no altitude)
Bluetooth connectivity, no need for cables
Configuration software (Linux software too) allows you to change everything about logging, data correction, elevation masks, SBAS (I haven't tried all these options). The logging control is great, the frequency can be set to anything from 1 sec to many hours
Linux driver to extract data (I have never managed to build this on Mac OS X); Gentoo Ebuilds for Linux driver and config tool

Bad things

No Mac software!
No indication of full memory (so I have to keep track and often get it wrong)
Indicator lights are counter-intuitive — when the green led is lit constantly, it is not locked onto a GPS signal. When it is flashing it has locked on and is recording.
Can't change the battery (built-in lithium ion). But I have opened it up and it would be easy to swap them if you had a spare.
need very much time for GPS-look. It flashes the green light, but it hasn't locked. Be careful with tracking!
software for download the datas works not satisfactorily under ~~Linux and~~ Windows-Pocket-PC (what's the problem?)

More info

Royaltek Gps Software

RoyalTek Vnus GPS-Mouse RGM-3600

SiRFstarIII GPS chipset
20 parallel channels
NMEA0183 compliant protocol
Multiple Connector Options(USB/Mini-USB/PS2)

RoyalTek RGM-3800

RoyalTek RGM-3800 with USB cable attached

SiRFstarIII GPS chipset
20 parallel channels, WAAS/EGNOS, DOP-Support (HDOP, VDOP, satellites, 2D/3D)
two standard alkaline AAA cells for about 12 hrs runtime
two rechargeable NiMH AAA cells for about 9 hrs runtime (an option not mentioned in the manual but it's been tried and tested)
size 34×24×64 mm without strap/belt, weight 68 g/42 g (with/without battery)
not waterproof, but fits easily inside a condom.
NMEA0183 compliant output
Mini-USB Connection to PC
Works with Linux (rgm3800py (german description), Jdatalog or rtkgps).
Works with MacOS/Linux including old PPC-Platform, if USB-RS232-Driver for Profilec PL2303 is available via this python-script http://code.google.com/p/rgm3800py/
Works with PocketPC http://aeropic.free.fr/RBT_2300/ (German, Spanish, Catalan, Hungarian version available. Windows-Desktop-versions available as well in those languages)
64 MiB flash memory for trackdata. Logging can be set in 5 levels (earlier units only offer the first three options out-of-the-box: get the firmware upgrade!).
- UTC Time, Longitude and Latitude
- UTC Time, Longitude, Latitude and Altitude
- UTC Time, Longitude, Latitude, Altitude and Velocity
- UTC Time, Longitude, Latitude, Altitude, Velocity and Distance
- UTC Time, Longitude, Latitude, Altitude, Velocity, Distance, Fixed Mode, Satellites, Fix, DOP and Course.
Comes with min. 5 sec interval - after an firmware upgrade 1 to 60 seconds interval is possible. In a car 1 sec. interval works fine, by foot or by bicycle better use longer intervals.
Recording interval and loglevel set by user. Defines range of memory.
Memory-Full Options: Stop / Overwrite
No button/key for marking waypoints, but each powercycling starts new track
Direct paththrough of live NMEA available :'GPS mouse mode' via USB-RS232.

See also: detailed german page for RGM 3800 at the OSM-wiki

Summary

Pro: tracks one of the best in SiRFstarIII-class (much better than RGM2300 or Garmin Etrex H family)
Pro: switch on, clip on and forget for the rest of the day.
Pro: standard batteries
Pro: big memory
Contra: no button for waypoints
Contra: downloading via USB can take several