Go and ask a pharmacist. They stock all of them and should give you a balanced view (if you think they are trustworthy) of which one has the best ingredients. These things tend to change over time too. When I was pg our pharmacist recommended a new one on the market at the time (I think it was called Fabfol?) as being slightly better than Elevit, but put Elevit a close second.

I figure most of the time it's not really giving me what I need and I'm just making expensive wee, but it doesn't hurt and if I do need a bit extra, then it might help. FWIW I got shocking leg cramps in my 2nd tri and my ob put me on to Blackmores magnesium tablets - fixed within a day. So they definitely can do something all those vitamins and minerals!