Since both the EFLS617SIW and the newer EFLS627UTT got excellent performance scores (as you'll see in the next section), there is likely something to Electrolux's SmartBoost feature, however gimmicky it sounds.
We judge a washer's performance using the normal cycle with a normal soil level, a hot water temperature and a high spin speed.. Within those parameters, we run three identical cycles with new stain strips and mechanical action strips each time.
Stain strips are pre-packaged, pre-soiled pieces of fabric we buy specifically for washer testing. Each stain strip has five sections, and each section is soiled with a different stain -- sebum (skin oil), carbon (mineral oil), pig's blood, cocoa (chocolate and milk) and aged red wine. After a cleaning cycle, we calculate how much of the original stain is left over. The lower the number, the better the score.
Electrolux's EFLS627UTT had only 36 percent of its original stains remaining. Most washers we've reviewed scored somewhere in the 46-48-percent range. The worst washer we've ever tested,, had 71 percent of its original stains remaining. Electrolux's older EFLS617SIW had 40 percent of its stains left over, on average, and the Samsung WF45M5500AZ had 44 percent of its stains remaining. Those are both very good scores, but the EFLS627UTT's score blows them away.
Mechanical action strips are thin squares of fabric with five holes pre-punched in the middle in the shape of an X. After going through a normal wash cycle, some threads inside each of the five holes begin to fray. We count the number of attached, frayed threads that measure at or over 2 millimeters long on each piece of fabric. The higher the number, the tougher that washer's normal cycle is on clothes.
We don't weigh this score as heavily as stain removal, since every washer we've tested also comes with a delicate cycle. That said, the EFLS627UTT had the highest wear and tear count to date -- 333 attached, frayed threads measured at or over 2 millimeters long. The Electrolux EFLS617SIW had a 295-count and Samsung's WF45M5500AZ had a 294-count. There is often a correlation between the stain removal score and the wear and tear score -- the better a washer removes stains, the tougher it is on clothes. That isn't always the case, but it's certainly true for the EFLS627UTT.
This wear and tear result isn't a deal breaker, unless you plan to wash delicate clothes using the normal cycle.
Buy it. Seriously, if you're looking for a front-load washer, the $1,349 EFLS627UTT (or white $1,199 EFLS627UIW) is an excellent choice. It removes stains better than any model we've tested, its well-designed display looks great and contributes strongly to its user-friendliness. The EFLS627UTT has a detergent pod dispenser, too, the first of its kind. Add in its premium dark gray finish, steam function and 15-minute "Fast Wash" cycle and you end up with a well-rounded washing machine that delivers in every category.