Given your tank's size, I think both pumps are way too big. Won't hurt anything, but will be more expensive to purchase, run and will heat the water to a greater extent.
With respect to quality and reliability, eheim universal hobby pumps are the pinnacle of small submersible pumps. I've had a 1250 running on a 20g nano since 2004 with no issues whatsoever.
Sicce Synchra Silent pumps are also extremely well thought-of. I've less long-term experience with them than the eheim hobby pumps, but I do run 4 of them on various tanks and they're dead silent, efficient, and well-built.
For your tank, I would choose the eheim 1250 in the universal hobby pump line, or the 1000 model in the compact series. If you want to go Sicce Synchra, I'd suggest the Sicce Synchra 1.5 or perhaps the 2.0 if you want to run reactors off of the return pump.
With respect to reactors, I'd strongly suggest running a separate pump. It makes maintenance much easier. I run mine with Sicce Synchra Silent 0.5 pumps; they're very efficient, relatively inexpensive, and extremely compact.
If you have some reason for wanting ultra-high turnover in your tank, and especially if you live in an area that has expensive electrical power, you might consider the EcoTech Vectra M1 DC controllable pump. They're definitely a more expensive option, but compared to the Sicce 4.0, it would provide the same flowrate at about half the amount of power. A bonus would be the ability to use EcoTech's battery back-up (the same one that's sold for the Vortech pumps). It's a more efficient option than a charger/inverter and a deep cycle marine battery, and it's also cheaper if you just want to provide flow in a power outage.