Which is better for long runs?

The New Balance 1080 v15. Its extra-soft Infinion foam and higher stack protect the legs over distance, while the Cloud X 4 is firmer and built for shorter gym sessions.

Which is better for the gym and HIIT?

The On Cloud X 4. The X-shaped Speedboard, midfoot cage and star lacing keep the foot stable during lateral moves like box jumps and mountain climbers.

Both use rubber outsoles and durable foams, so wear depends on use. The 1080's soft foam compresses faster under heavy mileage; the Cloud X 4's firmer midsole holds up well in the gym but its mesh upper sees more abrasion.

Is the 1080 v15 worth stepping up to over the Cloud X 4?

Only if road running is your priority. If you split time between the gym and short runs, the Cloud X 4 covers more ground; if you log long easy miles, the 1080's cushioning is the better match.

Does the 1080 v15 come in wide sizes?

Yes. It is offered in narrow, normal, wide and extra wide, which the Cloud X 4 does not match.

Can the Cloud X 4 handle daily running?

For short, easy runs, yes. For high weekly mileage or long runs, its firmer cushioning is less comfortable than the 1080 v15.

New Balance 1080 v15 vs On Cloud X 4

Buy the New Balance 1080 v15 if your main goal is long, easy road miles in soft cushioning. Buy the On Cloud X 4 if you train in the gym and want one flexible shoe for HIIT, lifting and short runs. The 1080 is the more plush, protective cruiser with a roomier fit and width options; the Cloud X 4 is lighter and more stable side to side, and its 4.5 out of 5 rating from 13 owners is solid but a small sample.

Choose the New Balance 1080 v15 if you run mostly on roads and want maximum soft cushioning for daily and long runs.
Choose the On Cloud X 4 if you do mixed gym training, HIIT and short runs and want a light, flexible shoe that handles lateral moves.

Prices

New Balance 1080 v15: $80.00 at eBay (last seen Nov 8)
On Cloud X 4: $99.95 at Swizvisa (last seen Nov 8)
Difference: the New Balance 1080 v15 is $19.95 cheaper than the On Cloud X 4 at the latest prices (Nov 8)