in the thunderbolts defense,most of the issues that stock phones are having are with verizon getting the network up and running,not with the phone itself. you can access the data via the programming menu if you want to toggle 3g only,and thats anotehr advantage to being rooted,some roms are adding 3g/4g toggle settings to the mobile networks menu
just depends on your wants and needs. the merge is going to be more of a middle entry,its not going to be a high end device. and i have my own reasons for not wanting any of the others
specs escape me for now,but the revolution has the worse camera of all the 1gh "superphones" at 5 megapixel.also,my experiences with the lg ally have somewhat made me question wether lg is really capable making a phone of that caliber. the X2... well,encrypted bootloader
to me,the phones worth waiting for are the ones that havent been anounced yet
but as i said,its a largely personal choice what you expect from your device.