Sony Ericsson Z600

this may be a dumb question- I work for t-mobile customer care and I have the t300, I am not sure why I purchased it as cust's do complain about the phone and it has a horrible time connecting. I know that off and on (Sony) Ericsson produces phones that are flukes-- bad phones. The R280 that I had when I had att back in '00 was a good phone and the t28 I stole from my dad is a good phone but my t300 sucks... compared to the t300, how is the z600? it is not offered by any us carriers and I do not know if t-mobile will get it and it is $440 and is a large investment, is it a solid phone? 😉