The 700 is better, if still on offer it appears decent for the cash.
My nephew has a b-twin, he loves it.
The only thing your money won’t buy you is credibility, because the btwin brand is looked down upon as being a poor mans entry level brand into the world of cycling.
In reality all bikes at this price point are manufactured in Taiwan with parts made by shimano, just come with fancier brand names.
It is a well specced bike for the money and Manitou are a brand on the up again and were around at the start of mtb suspension, and it looks good.
More rings, means more weight – two rings is plenty.