I can't give an opinion on many ROMs yet. However, I've been using Synergy for a couple days now and I haven't noticed a bug yet. Wireless Tether is built in, cool boot animations, and the battery life has been amazing. With stock rom I was normally under 20% at lunch time with standard battery. With Synergy up and running I unplugged at 11pm last night, here I am nearly 5pm and still have 42%! Been a slow day at work so I have been using my phone quite a bit to kill time to. I use google voice so I can not vouch for the VM notifications though.
Make sure you have an gingerbread compatible radio installed, or ready to install.