DW vs. Horst Link Suspension

I'm looking for opinions on DW vs. Horst link. I have the opportunity to purchase a new Pivot Mach 4 for lots of $$$ or a used Titus Racer X at a MUCH lower price. While I have the money for the new Pivot, it would be a real budget stretcher.

Short, steep hills have been my nemesis on my hardtail - both up & down. I have trouble powering uphill & the front wheel dances all over, making it difficult to steer. Downhill, I often feel insecure - as if the back wheel could lift at any moment.

I had the opportunity to ride a Pivot on some pretty technical terrain today and it was AWESOME. It climbed like a mountain goat. The front wheel didn't dance as much going uphill & I never felt like the back wheel was going to lift on the downhills. It also rolled over decent size rocks & ledges like a champ.

I am sure that much of the difference in the security that I felt on the Pivot was due to the better traction offered by FS vs. the hardtail. It is also possible that the Pivot felt more secure because its a better size for me. The hardtail is a little too big. The Titus I'm looking at is a comparable size to the Pivot I rode.

Anyway, I've heard that the DW's claim to fame is in its pedaling efficiency. Pedaling efficiency & security on hills are priorities for me. Does anyone have an opinion on whether the Horst link on the Titus is significantly less efficient than the Pivot, or whether the Titus feels less secure on steep hills? I'm asking because I would not have the opportunity to test ride the Titus before buying it.