What They Have in Common
Both are three-wheel push carts. Both include an umbrella holder — detachable on the Bag Boy, adjustable on the Sun Mountain. Both carry a two-to-three year warranty on some portion of the cart. That's about where the overlap ends — the Compact 3 has a long list of published specs and included accessories; the Speed Cart X's published data is thin.
Where They Differ
Size and weight
The Compact 3 weighs 13.5 lbs and folds to 21.5 × 13 × 18 in — 2.9 cubic feet. The longest single dimension is 21.5 in, which is the number to measure against your trunk floor before you buy. The front wheel tucks under on the fold.
The Speed Cart X weighs 18.6 lbs. Sun Mountain doesn't publish a folded size for it. That 5.1 lb gap is real and it shows up every time the cart goes in and out of the trunk. Whether the Speed Cart X folds smaller, larger, or about the same as the Compact 3, there's no published figure to say.
What's in the box
The Compact 3 includes a cup holder, a deep scorecard console, a detachable umbrella holder, and integrated umbrella storage. The Top-Lok bag retention system is part of the cart.
The Speed Cart X includes an adjustable umbrella holder and a magnetic rangefinder plate. Cup holder and storage console aren't listed. Whether that means they're absent or just unpublished, Sun Mountain doesn't say, so you'd want to confirm before you order.
Build and warranty
The Speed Cart X's pitch is in its hardware: stainless-steel fasteners and bearings, and an upgraded brake cable. The Compact 3 has a handle-mounted parking brake; the Speed Cart X doesn't publish a brake type at all. Sun Mountain also doesn't publish a fold mechanism or bag-retention detail, which makes those real differences to sort out before buying.
On warranty, the Speed Cart X wins in one direction: it covers the frame for three years, with one year on other parts. The Compact 3 carries a two-year limited warranty.
Price
The Compact 3 lists at $259.95. The Speed Cart X lists at $299.99, a $40.04 gap at list. For the extra $40 you get a longer frame warranty and stainless-steel fasteners and bearings. You give up 5.1 lbs and a published folded size.
Who Should Buy Which
Get the Bag Boy Compact 3 if:
- You want to know how small the cart folds before it arrives at your door
- You're lifting it in and out of a sedan trunk or a tighter cargo area and 13.5 lbs is the weight you're planning around
- The cup holder and scorecard console being in the box matters — not as add-ons, not as accessories to track down separately
- You're on a push-cart budget and $259.95 is already stretching it
Get the Sun Mountain Speed Cart X if:
- Hardware is the thing you're buying for — stainless fasteners and bearings are a real spec, and the three-year frame warranty backs it up
- You've already seen the cart in person, or you've got a way to confirm the folded size and accessory situation before committing
- The extra $40 at list is not a factor and you'd rather pay for what's inside the cart than what ships in the box with it
The Bottom Line
The Speed Cart X has stainless-steel hardware and a stronger frame warranty. If you've held one, know how it folds, and are comfortable with the gaps in the published data, it might be the right cart. But the Compact 3 is 5.1 lbs lighter, $40.04 cheaper at list, folds to a known size you can measure against your car, and arrives with the accessories already in the box. That's a lot to give up for specs that Sun Mountain hasn't fully published.
Get the Bag Boy Compact 3.