I wasn't sure where to post this question so I will apologize in advance if it shouldn't be here. My husband and I are going to London for vacation and then we plan on taking the Eurostar to Paris for a few days and then back to London. Should we purchase Eurostar tickets here in the US or wait and purchase in London? Also, is there any special Eurostar prices other then the Us Air promo (we are flying Virgin)? Is first class worth the extra cost? Thanks.