VPS vs shared hosting for Xaraya

Hi everyone,

I currently run two small community Xaraya websites.

250 total users.
20 concurrent users throughout the day
16 forum posts on average per day.

8000 hits per day (of which about 1500 appear to be by actual people, the
rest bots)

The user base and site usage will remain constant for the foreseeable future
(i.e. the site is not growing or shrinking).

I have the sites running on a server in my home due to dissatisfaction with
performance and downtime from my previous shared hosting experience...

However, after my own troubles and downtime due to my own failed hard disks
and routers, I'd like to move the websites back onto shared hosting or a VPS
so that someone else takes care of the hardware side of things...

Question:

A VPS is attractive as the bandwidth, CPU, and memory are allotted to my
site and guaranteed.. so I don't have to worry about poorly programmed or
bandwidth hogging sites on the same server...

However, I'm not sure how much memory I need to run the site at a decent
speed.

VPS's seem to come in flavors of 256mb, 512mb, 1gb plus.

Assuming the number of users and usage mentioned above, Would 256mb of
memory be sufficient to run the site,
or would I be far better served with 512 mb?

Do any of you guys have experience with and can recommend a solid,
affordable VPS hosting provider?

Or if you run a similarly trafficked site on Shared Hosting and are very
happy with your hosting provider's stability
and performance can you recommend a shared host?

Thanks so much!

Stein Setvik