Re: RG1420F vs RG655
Do you want HH or HSH? Edge pro is known to be a very good Bridge but the 655 has the Original Edge. I've never used an Edge pro so I can't personally speak to it's quality.
The RG655 is basically a 550 with AANJ and full dimarzio pups (Air norton, True velvet, Tone Zone) and the Prestige wizard neck.
IMO, if you want versatility, 655. If you want a nicer flame top and only 2 Humbuckers, get the 1420F. Personally I like them both but I have so many HSH I'd choose the 1420F.
Also, are you buying the 1420F new or used?