Just info sharing on my opinions of some mods to our ride.
I'm a firm believer in a good handling coach, as even these big rigs can get you out of trouble - if they can maneuver as nimbly as possible
When we first bought out coach, we installed Road King's on all 6 positions. Added stiffer walled Michelin XZE*'s. And added Super Steer Motion Control Units (MCU's) front and back.
I've mentioned here and on other boards, that I felt the Koni SP3's would have been a good shock to add to the four rear positions - timing wise, these came out about 4 months after my decision. (And many thanks, and a salute, to Justin at Koni for very straightforward advice for our IFS coach!) And probably would have been a good shock for the front too. I like the Road Kings, and these were 2 1/2" generation before the 3" came out. Valving can be tuned, if needed, with the help of Road King. Sure not saying Road Kings are not a good shock, but, they are for sure more expensive
OK - So now as of the last 2 months, we've made two changes that impact both handling and road ride comfort:
1) We replaced two pot hole damaged Michelin XZE* tires. (Reminder, the "*" adds more meat to an already robust XXZE tires, to handle fleet delivery 'curb scrubbing +'. So on a front end, these really added to a bit stiffness to the ride. Especially on expansion joints and rough roads. And yes, a bit more sure footed for those emergency turns, if ever needed, that I add value to.) We replaced them with two BF Goodrich ST230, a Tier 2 tire, as that was the only tire in the 12R size I could find during the overall shortage sparked by the Michelin supply problem. (Yeah, another opinion, Michelin sure blew the forecast on demand. Missed several sales in what I'm sure is a slower market of RV's, vs trucking. But dang it, a lost sale is not just a loss of sale this time around. But also possibly future sales, as buyers form new tire loyalties.)
The BF Goodrich is a well known tire, Michelin built, and provides a great bang for the buck - especially with FMCA group purchase prices
2) Source Engineering has a 'better design, and more sophisticated' 'air check valve' - with their Comfort Control Valves. The Super Steer MCU's were the only game in town at the time I was researching. And, they do a good job of improving handling, and the Walmart Wobble. I liked them, because the 'set' the coach faster in left to right body shifts, lie on mountain S curves, and emergency lane changes. But, they also paid the price by adding to a stiffer ride. The MCU's restrict rapid air flow in both directions.
Enter the Source Engineering Comfort Control Valves. And well, you get the same good control, but also get improved comfort. The CCV's only restrict, control, air in one direction. So, if you hit an expansion joint, a pot hole, bump - they do not impact what the normal air bag suspension bring to the ride - comfort. They restrict air flow in one direction, which still helps in handling and 'setting' the suspension faster.
OK, so along post, again
I give it these mod's the Goldilocks ratings:
1) BF Goodrich ST230's (Or other higher Tier 2 and Tier 1 tires without supper stiff sidewalls.)
2) Source Engineering Comfort Control Valves.
They provide a 'just right' balance firmness and support, while not being too jarring of a sleep, I meant ride
And again another yeah, I do like the Road Kings, but suspect with the current front end valving - this too adds to a bit stiffer ride. But, with the payoff in superior handling and coach control. Kong SP3's? Especially on the front end of a larger IFS coach - probably better then most, and a bit softer ride, but without as much control as the Road Kings.
Opinions will vary, those are mine
Best to all. Be safe, have fun,