Nseries problem?

i have a N73 phone. i like it because it has a lot of function. but when the memory is already full, opening messages could take like more than a minute. but all in all, its OK. but i would prefer to buy (next time) a Sony Ericson k800i. they say it has the same features with Nokia n73, and the pictures look better and it doesnt hang. :D

I have an n75 and recently it's began to lag when opening messages, not always but often enough to be really annoying. It takes maybe 20 seconds to open a message that would open instantly before. BUT, let's take into consideration that I have nearly 700 messages in my Inbox! I think clearing it out would help me tremendously. Also the n75 sometimes has memory full errors which I highly dislike, and sometimes I reboot the phone to fix them. Other times, they just go away after closing and reopening an app; say, Web. Buy an nseries, you won't regret it. Preferably, an n95 :)