After my other charger (Numax) started making my smaller 7ah sealed lead acid battery bubble and get warm I checked the voltage during bulk charge and it was putting out 14.7v!
Took it back and got one of these CTEK's instead and wow this thing is much better than my old charger. It has indicator LED's to show what stage in the charge it is at so you can get an idea how long is left to go. I put it on one of my 12v 7ah sealed lead acid battery's and checked how the charge progress was going every hour or so. There was no bubbling to be heard and the battery stayed nice and cool.
It took around 12 hours to charge a fully discharged 7ah 12v sealed lead acid battery (normally I would not run them down this far but it was put on a load test to make sure the other charger had not damaged it).
Overall I would recommend the XS 0.8 for smaller lead acids (the manual says it will bulk charge upto 32Ah and under), for the sealed types especially as its 6 step smart charging really helps when charging them.