Harry's GPS Laptimer

Is anyone using Harry's GPS Laptimer?
Is it any good?
What do people recommend?
Who uses a GPS receiver and is the one recommended by Harry's (XGPS150a) any good?

The daul xgps is very good, don't really use Harry's any more though as I have cheap android phone I use with race chrono to save my expensive iPhone from getting trashed. When I did use it worked very well, and the way you can analyse the data after is useful too. Rave chrono is far simpler to use though.

I'm struggling with Harry's. My version seems different to Nigel's and I've only managed to log one lap from 3 days! Going to perserve in Spain though

Harry's can be really good or very frustrating. Best way thing to do is pull the sim card out of the iphone, make sure all other apps are closed and the auto lock is turned off. I have a XGPS150a I want to sell as I bought a AIM Solo. It's in perfect condition so make me an offer.