I don't think anyone can advise you on that because the ports are so different. It depends on your priorities of the area you would like to see. Toss a coin and do one now and the other later!!! The other option is to do the Baltic and then do the British Isles by car or land tour when you disembark. (unless time is of the essence)

If they are both Regent and on the same ship, then pick the group of ports that you like the best. Otherwise, I don't see what I could say.

I'd pick the longer one!

"The other is for July 2011 for 12 nights and covers Stockholm, Finland, Russia, Estonia, Latvia, Poland, Germany, Denmark, Amsterdam, Belgium and disembarks in London."

We just did a similar itinerary on Celebrity out of Amsterdam and I would highly recommend it as an option. Of the cities we visited - Stockholm, Warnemunde, Copenhagem, Tallinn, Helsinki, St. Petersburg, & Amsterdam - only St. Petersburg requires a tour. If you are comfortable walking around on your own all of those I visited are reasonably compact cities with central areas that can easily be accessed from the ship shuttle drop off point.

The London/Scotland/Wales/Ireland itinerary can best be seen, IMHO, in another fashion either at once or reasonably easy trips using rail or car transportation.

Many of the cities on the Baltic itinerary are not easy to see on one trip except by cruise ship. Not sure of your age or travel situation, but England and Ireland are "easier" trips to arrange on your own of for shorter periods of time.

I posted a trip report which may give you a sense of what to expect.

Always pick itenary first. So, what do you want to see? UK or Europe?

I agree with Ryan--the UK can be better seen by land, it's less likely you would do a land trip to the Baltic, so I would choose that one. Although I'd have to see the actual list of ports on the UK one--I have looked at these in the past and some of the itineraries look quite nice (I'm a Regent cruiser, but have not done either itinerary.)

I would go with the cruise #1, and the only reason is: I don't want to visit 11 countries in 12 days! They will all get mixed up in my head

Go to the destinations you will see the most right out of the port and will be less likely to return and want to explore further. Hence, this is such a no brainer; go on the July 2011 cruise.

Why cruise the British Isles? It is very easy to drive around Great Britain and so much to see. A cruise simply doesn't do it.

If you take a baltic cruise, make sure you stay at least 3 nites in st. petersburg so you have enough time to see st. petersburg and moscow.

If you do the Baltic, I recomend Regent Cruise Line. I sailed on the Navigator, 2 years ago. I have nothing but great things to say about Regent. From meeting the hostess at the hotel (who found my luggage before sailing) to all the crew members. Our suite was wonderful and the balcony was so nice to be on when coming into port, and able to open for fresh air. Food was top draw, not a bad meal for the whole cruise.
I have done the Baltic 2 times, with a ten year span. Both times we hit a heat wave and sailed in July.
If you don't want to drive the British Isles, I recommend taking a Tauck tour, I have taken sevral and would not use
another tour operator. Tauck Tours has been around for years, started out just doing the Fall Foilage tours. The company
is still family own. You might look to see if they use Regent for a Baltic trip.
Hope this helps BJ

We did the British Isles twice, both times on a Trafalgar motorcoach tour. That's my recommendation for seeing the British Isles. We saw London, Stonehenge, castles, cathedrals, the English, Scottish, Welsh, and Irish countrysides, pretty villages, and too many wonderful things to list here. Motorcoach touring is special in that you get to be one big happy family with your fellow travelers. We like motorcoach touring every bit as well as cruising, and we totally love cruising.