Ive done a lot of reading since my last post. Ive decided (99.9%) sure to go with a hybrid (silicone/polyurethane) sealant/adhesive. We have to hold on to our wallet though because a tube is anywhere from 9.00 to 13.00
I dont think we will regret spending the extra money on a higher quality product that is known to give excellent results
Some more information I found on another site...
Finding a solution to some of the shortcomings of field-applied liquid sealants (principally those related to workmanship and dependence for performance on resistance to tensile stresses) was the cornerstone of hybrid sealant research that began in the early 1980ís. The product that resulted from this research combines ultra-low-modulus silicone and impregnated open-cell foam. The combination is a preformed sealant with movement and sealant performance exceeding that of either component used alone. Unanticipated additional benefits of the hybrid resulted from its thermal-insulating and non-invasive anchoring properties.
More than two decades of successful performance, evaluation and refinement have proved the hybrid sealantís increasing versatility in addressing larger and also dynamic-movement joints. Evolution in materials and manufacturing technique show the promise of new hybrids for use in still broader and more demanding applications. Additionally, hybrids as alternatives to conventional field-applied liquid sealant use in low-movement or non-moving applications are likely to become available in the near future.
Keywords: liquid sealant, impregnated-foam sealant, hybrid sealant, tensile stresses