So I'm thinking of buying both these games but I have some questions before I buy them.

DQ8 supposely have random encounters and they are quite frequent. I find those quite annoying. The game is difficult and veteran jrpg gamers will love it according to gametrailers, and I usually dont mind some challenge. I like jrpgs and the ones I've finnished are following:

Persona 3 FES

Final Fantasy VII, X, XII,

Tales of Symphonia

The World Ends With You

Am I experienced enough to handle DQ8? So if it's difficult is the story engaging enough to make you want to continue and how do you find the characters? good/bad etc? The only DQ I've played is Dragon Quest: Monsters on NDS and it was fun.

About VP2: Slimeria:

I never played the original on the PS1. Is the stories related? How is the characters? Is there good characters development? Story? The grinding, good or bad?

Strife

Yes. You can handle DQ8.
Also, at a certain point, you can gain a spell that reduces random encounters significantly (those with much lower-ranked creates).

Mike from Morgantown

Yes, you can handle DQ8. You have to grind for the first boss, but it becomes easier from then on out.

I haven't played DQ8 or VP yet. The reviews are all pretty epic for DQ8 though, and the music is awesome! That's one thing I can say about the game. Have a few tunes DLed from the soundtrack. :P I'm looking forward to playing it.

About Valkyrie Profile Silmeria... I'm pretty sure there are quite a few tie-ins with the previous VP in the plot. (If I remember a certain review correctly!) Having the first one under your belt would be beneficial.

The first one runs crazy high on Ebay for the Playstation, however Valkyrie Profile Lenneth is pretty much the same game with improvements on the PSP, and you can find it for about 25 bucks used in great condition. (IF ya have a psp!)

Sorry I can't be of more use.

I assume you gain it pretty far into the game?

Having loved all the RPGs you listed except Symphonia which I haven't played, I can tell you that DQ8 is the worst RPG I've ever played and that everything in that game is broken beyond hope. I can't find one game I hated more than DQ8, and I wouldn't recommend it to anyone. The story is only a collection of clichés and fetch quest without any interesting plot or characters whatsoever, and the gameplay is very shallow and it resorts much more to grinding over strategy and planning. Whether you take my advice or not is your choice.

Haven't played VP2, though

in DQ8 the first middle and last boss are solid and takes a lot of grinding the rest doesn't have too much grinding and if you like exploring I found that just by exploring you normally leveled up enough. I love this game and only found it frustrating for very small amounts of time. I don't think there are any more random encounters than FF7. I know that there are very different opinions to mine of this game though