I depends on where you are. I would probably look at the NGuard first. The main reason is that they fall under the state first. You are subject to the indivual states rules. For example, most states have a 2-3 year mandatory dwell time after a deployment. The reserves......unless they need you. Also in the reserves you can be plucked out and assigned to go with any unit, or backfill for a dentist that is deploying. For example you might be called to AD and assigned to a unit from Alabama that needs a dentist. The NG generally goes as an entire unit, and I don't think they can use you as a backfill to another state. I know there's always exceptions, but if you look at the 2 side by side, the NG seems a little nicer.
I'm also not sure about the reserves Bonus it was 10k but that may have changed in the last couple months. The NG is 25k a year for 3 years plus drill pay....$630 per weekend.
I'm not an expert, but I have sat down with both retention recruiters and looked at the pros and cons, and it seemed to me that the NG was a better deal.