The Tale Of A Choice Between Two Skimmers

So I definitely have an undersized skimmer and am looking to upgrade. Here's the decision to be made - I currently run a sumpless 55gal with an HOB skimmer. In the relatively near future I'll be switching to a 55gal with sump and Calfo 'coast to coast' overflow. Do I make do with my current skimmer and buy an in-sump model for my future setup or do I get a better HOB skimmer for my current/future setup.

Now the obvious answer for me is to say in-sump for a multitude of reasons. But there are a couple key benefits (at least in my eyes) of going with an HOB skimmer. The most obvious is I can use the upgraded skimmer on my current system and start keeping a cleaner reef environment for my pricey acros.

The second benefit I see to an HOB is the possibility of running it out of the overflow on my future setup. Calfo talked about feeding your skimmer with the dirtiest tank water you can to get the best efficiency. The water will be it's dirtiest in the overflow and given the design of a 'coast to coast' overflow box it would be easy to install one on the back of the tank inside the box. Im not sure if this would work in reality so any feedback on the idea would be appreciated - in theory it sounds good to me though.

Or am I going to be happier down the road with an in-sump skimmer?