Ok, I haven't had much opportunity to test because of the snow in the UK but have now done three short journeys.

Firstly, the software has some great features and I say that coming from the voice guidance software that I previously had on the Nokia N95. I haven't had a dedicated Sat Nav before so can't really make a comparison.

There are loads of features, too numerous to go into in a shortish posting, but comparing the old Nokia software with the sygic is almost like comparing an old BMW with a new one with lots of gadgets.

I don't want to actually review the product as it would take too long to do and I just don't have the time to do it.

But I will get straight to the point and comment on the weaknesses. This is not an attack on the product as I do think it is very good and I like much of it.

However, one of the annoyances is that it is not overtly easy to switch between applications with the sat nav running as it runs in full screen and I couldn't find a way to flick quickly to another app. As far as I can tell, the only way to do this using the sygic menus is to close the sat nav down entirely.

A way around this is to click the top button on the n900 and select phone and then minimise that and you can then browse through other apps keeping the sat nav open.

But for me, the deal breaker could well be the next, and for me the most important point. There seems to be a lag in the voice and maps. The old Nokia N95 sat nav maps were generally 'spot on' when the voice said, "turn right" you could guarantee you were right at the point that you needed to do so.

The sygic however, has told me to make a turn in x amount of yards - but then I have actually taken the turn and gone about 50 yards before the map updated. (Good job I knew where I was going).

Perhaps might this be down to conditions? I don't know but I never had that problem with my N95 unless I had lost the GPS altogether.

For me this is the most vital part of the sat nav and even though the Sygic app is crammed with useful features that would usually win me over - the apparent lag between voice and map from time to time (on the shortest of journeys - 1.8 miles) is enough for me to have second thoughts about purchasing this and buying a dedicated sat nav instead.

To be fair in this process I have to go to London on the weekend and I will drive in and out and then make any additional comments regarding the lag.