The one I started out with is a Dowelmax, absolutely top notch engineering and precision every time. I have used it for hundreds of 10mm dowels and I can honestly say that I have never had a problem with alignment. This gives an idea,What are your dowel jigs?
The only issue is that it can be a slow process, not so much the drilling but the gluing and insertion of all the dowels followed by clamping within the open time of the glue. I went down the route of buying a Domino XL700 in the hope of a faster method but although it makes a nice oblong hole with a precise depth I have found getting precise location to be hit and miss which is no good because you have to re make that part. They do provide a sloppy setting which helps with alignment but not for me.
So more recently I went for the Jessem doweling jig which is a cheaper option than a dowelmax because it comes with 6,8, 10 and 12 mm drill guides unlike the Dowelmax that comes with just 10mm but you can buy the others. Everything is give and take, the dowelmax has the clamping built in, the Jessem you need to clamp but the one thing that I do like about the Jessem is you can not only offset the drill guide without unclamping it from the workpiece but also in 2mm increments which gives better flexability when it comes to your dowel pattern.
This thread was something I posted giving a comparison, Dowelmax, Jessem and XL700