Hi Greg, I'm not sure about the Legend as the reviews have been very mixed and I've not stayed there myself. However it's certainly more central to most of the attractions in the province than the Emeralda is, although the Emeralda does have benefit of providing resort facilities.
I read fairly recently that another 4*-ish hotel has opened in Ninh Binh town, but being an absent-minded old trout I forget to write down its name. Sorry. Failing that, it seems that a small number of 3* establishments have sprung up recently. Am looking forward to trying out at least one of them this March/April.
I can provide Toan's contact details here on the forum, because (1) I have no financial/commercial interest in his very small, one-man business, and (2) I've always found him to be a cracking good guide and am therefore happy to recommend him. Email firstname.lastname@example.org, mobile no. 0988 8995266. I gather that he can rope in other safe riders when required, but he retains responsibility for the actual guiding.