Senix 21 in 170cc FWD A025054-A
A 3-in-1 self-propelled mower for flat lawns with lots of trees and beds to steer around.
Amazon $392.45$392.45
The Senix 21 in 170cc FWD A025054-A is the better lawn mower overall, rated 3.6 to 3.4. The Senix 21 in 170cc FWD A025054-A leads on cutting modes and power. The PowerSmart B8721S1 Self-Propelled costs $12.46 less ($379.99 vs $392.45).
PowerSmart B8721S1 Self-Propelled
#14 in Self-propelledFull review
A low cost rear wheel drive mower with a name brand engine, for sloped lawns up to a third of an acre that you bag or mulch.
Amazon $389.99 PowerSmart $379.99$379.99
Prices were last checked October 31, 2026 and are subject to change; the price and availability shown by the retailer at the time of purchase apply.
Which should you buy?
- Choose the Senix 21 in 170cc FWD A025054-A for cutting modes (3 ways to cut: bag, mulch, side discharge vs 2 ways to cut: bag, mulch) and power (170 cc engine vs 140 cc engine).
Scores side by side
Each factor is scored 0-100 against the same fixed reference points for every self-propelled lawn mower; a clear win is highlighted. How we rank explains each one.
| Factor weight | Senix 21 in 170cc FWD A025054-A | PowerSmart B8721S1 Self-Propelled |
|---|---|---|
| Overall rating | 3.6/5 | 3.4/5 |
| Value 30% | 95 $18.69 per inch of deck ($392.45, 21 in deck) | 99 $18.09 per inch of deck ($379.99, 21 in deck) |
| Deck 20% | 12 21 in deck | 12 21 in deck |
| Power 15% | 62 170 cc engine | 25 140 cc engine |
| Cutting modes 15% | 100 3 ways to cut: bag, mulch, side discharge | 50 2 ways to cut: bag, mulch |
| Warranty 20% | 25 2-year warranty | 50 warranty not published (neutral score used) |
Specifications
| Senix 21 in 170cc FWD A025054-A | PowerSmart B8721S1 Self-Propelled | |
|---|---|---|
| Cutting | ||
| Deck width | 21 in | 21 in |
| Deck | Steel | Steel |
| Cutting height | 1.2 to 3.8 in, 6 positions | 1.5 to 3.9 in, 6 positions |
| Bag | Yes | Yes |
| Bag capacity | 1.7 bushels | 1.7 bushels |
| Mulch | Yes | Yes |
| Side discharge | Yes | No |
| Power | ||
| Power | Gas | Gas |
| Engine or battery | 170 cc | 140 cc (Briggs & Stratton E550) |
| Electric start | - | No |
| Build | ||
| Drive | Front-wheel drive | Rear-wheel drive |
| Weight | 61.7 lb | 70 lb |
| Warranty | 2 years | - |