Hi WayneF,
The upper layers of a mattress are generally the weakest link of a mattress in terms of durability and are the layers where the quality/durability of the materials is particularly important. A mattress will tend to soften and break down from the top layers down because the regular deflection/compression of the upper foam materials and components when you sleep on the mattress is what softens or breaks down the materials over time and foam softening leads to the loss of comfort and support which is the most common reason that a mattress will need to be replaced. The softer upper layers of a mattress will deflect and compress more deeply and more often than the firmer deeper layers and components in a mattress such as the innerspring so a good quality innerspring of any kind wouldn’t generally be the weakest link in a mattress and wouldn’t be a concern in terms of durability … although it can certainly make a difference in the “feel” and performance of a mattress.
Having said that … the Holland Maid offset coils are a high quality, strong, and durable component. There is more information about the different types of innersprings in this article and in post #10 here.
Outside of the innerspring itself … the Parklane Weidler uses high quality/density and durable materials above the innerspring as well so there are no lower quality materials or “weak links” that would compromise the durability or useful life of the mattress and if you have confirmed that it’s a good “match” for you in terms of comfort, firmness, and PPP (Posture and alignment, Pressure relief, and your Personal preferences) and it compares well to your other finalists based on all the other parts of your personal value equation that are important to you then it would make a great quality/value choice.
As you probably know … Parklane is also a member of this site which means I think highly of them and that I believe that they compete well with the best in the industry in terms of their quality, value, service, knowledge, and transparency.
Phoenix