XSPC's make one of the best compressions....
If you dont like them, there isnt much others you will like...
Sigh...
If your having a hard time sliding the compression over, its fine to use diluted soap water, your not using it inside the tubing, your only using it as a lube to slide the compression over.
However as Stefan also stated, sometimes just distilled water will be enough.... its up to you and your judgement.... but the tubing isnt too pourous to the point where using soap water on the OUTSIDE of the tubing will contaminate your loop.
You can get:
Bitspower: _dont like these, the xspcs have a notch in the barb area for a quarter to tighten, these dont, and as others stated, you need a large hex wrench.
https://www.amazon.com/Bitspower-Compression-Fitting-Tubing-Ultimate/dp/B01LYH8DZT/ref=sr_1_9?ie=UTF8&qid=1534545809&sr=8-9&keywords=bitspower+compression+fittings&th=1
Swiftech: These a bit more bulkier then the XSPC's
https://www.amazon.com/Swiftech-Lok...sr=1-4&keywords=swiftech+compression+fittings
Barrow: Pretty much identical to XSPC's...
https://www.amazon.com/Barrow-Compr...4&sr=1-4&keywords=barrow+compression+fittings
Monsoon: I really like these, however they are very pricey, but they come with tools.
https://www.amazon.com/Monsoon-Cent...&sr=1-5&keywords=monsoon+compression+fittings
Koolance: (meh... id honestly look past these... they are soso.... barrow or xspc's would honestly be my first recomendations)
https://www.amazon.com/Koolance-Com...&keywords=koolance+compression+fittings&psc=1
EK: (id only buy these if you wanted the unique colors which monsoon's didnt offer...)
https://www.amazon.com/EKWB-EK-ACF-...&sr=1-7&keywords=ek+compression+fittings+soft