My current shimano 545's have disintegrated - possibly due to lack of maintenance and bashing them on too many rocks. I need to replace them but is it worth spending the extra and going for the 646's instead ?

Is the quality of manufacture better ? Better sealing and bearings ? Will i be able tell they are a more expensive pedal ?

If you don't need the cages try the 536's I have 2 pairs and they are pretty good, look a bit ugly but are cheap, around 30 quid.

Just a thought!

AP

P.S. The cages on my 545's rattled off eventually but I still use them now I have sawed the cages off!

Hmmmm. 646's weigh a ton.
I've got 545's currently, but don't really like them. I actually prefered the 434's I had before them. Which is what I'd suggest. Cheaper than the 545's, lighter and actually more grippy. Plus you can use any leftover bits of your 545's as spares.
536's are also very nice, and I've got a set of those too. Unless you plan on using the platform lots they are the best option I reckon......

I've got a pair of 646's for sale - £30 - good condition -just expected scratches - email me if interested.

My 545s have had major cage problems too, i've taken them apart many times to bodge up for another few months. There are a couple of design flaws that mean the cage will always come loose. They have a spline into real monkey-metal with only 1mm engagement depth. That's on the outer side, and after hitting a couple of rocks that'll be wobbling all over the place, then on the inside they have a plastic collar that the metal cage rotates over. Bad idea, cos as soon as mud gets in the plastic gets ground to shreds, and that side goes rattly too.

Basically they suck.

And then there's those stupid cage bolts that do nothing - what's that all about?!

I would wan't to take a good look at the exploded diagram of the 646 before saying they are any better, and it's not available from shimano's website.

I have VP DH caged SPDs - had them two years no probs and cost alot less. Will go for them again over Shimanos as they are basically copies.